50 Gallon Tank Let’s talk about “stress cysts”

Posting this because I’ve had a couple instances already since i restarted this 50 gallon and got new fish.
The fish look completely healthy at the LFS, then you bring them home and you notice little white spots. Think it’s ich? i sure did.
Especially because ich becomes prevalent on stressed fish, it’s most likely to happen when bringing them home from the LFS since that puts a great deal of stress on them.
First, it was my orange platy. he developed a white spot on his tail and went straight to quarantine because i hadn’t noticed it before. it stayed there for over 72 hours, and with the help of someone on this forum it was confirmed to be a cyst and not ich, since ich’s white spots typically disappear and reappear in different places as the parasite reproduces, there also usually isn’t just one spot. This was just one spot that stayed there for several days; it’s gone away now.
Second incident is in my latest fish: 2 angelfish i got over a week ago. at the LFS, and even in the “transfer bag” there were no signs of spots. Put them in the main tank for only 3 hours then i noticed a few spots on them so i put them in the quarantine (i know, i should’ve quarantined them to begin with. rookie mistake. Still learning a lot from fishlore lol) but a day later and the spots are gone, they haven’t returned. the angels are perfectly healthy, always hungry and excited to see me. No symptoms of ich as i prepare to return them to the main tank.
Are these cysts due to stress, but isn’t really ich? I’ve heard of a mysterious phenomenon called “stress ich” but when i search it on google it’s just pages and pages of how to treat real ich. I’ve also heard that fish can cure ich all by themselves without treatment if it’s not very severe, and fish that are not stressed can typically hold off ich and it’s symptoms as long as their immune function is optimal.
I’ve seen no signs of any other spots or ich in my main 50 gal. Side note: I actually have another platy i brought home with part of his tail gone and it’s healed almost completely in the month i’ve had him. (Very proud and happy about that)
What do you guys think?
are “stress cysts” a real thing?

 

Stress can certainly cause acne and various other things in humans, so why not fish?

Never experienced these cysts on my fish, but it might also help that all the places in town to buy fish are generally within a 10-15 minute drive from my house, so transit time is limited, which probably helps. That, and usually i am not buying fish very often at all! I will take note to make observations though, as i will be buying quite a few fish in next few months.

 

Stress can certainly cause acne and various other things in humans, so why not fish?

Never experienced these cysts on my fish, but it might also help that all the places in town to buy fish are generally within a 10-15 minute drive from my house, so transit time is limited, which probably helps. That, and usually i am not buying fish very often at all! I will take note to make observations though, as i will be buying quite a few fish in next few months.

My LFS are approx 20-30 minutes away. But a little time can perhaps make a big difference i suppose

 

There is a disease called epistylis which looks similar to ich but is not ich. Is caused by cilliates. Is treated with salt or formalin.

 

There is a disease called epistylis which looks similar to ich but is not ich. Is caused by cilliates. Is treated with salt or formalin.

Does this disease tend to disappear quickly? these spots went away only a day later after they appeared on my angels. Didn’t treat them with anything, though i use small amounts of aquarium salt at times.